JPS638473B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a photoreceptor cleaning member used for removing residual toner on the surface of a photoreceptor in an electrophotographic apparatus.

As a photoreceptor cleaning member for an electrophotographic device, for example, a roller-type cleaning member disclosed in Patent Application Publication No. 127240 of 1972 has a structure in which the peripheral surface of an elastic cylindrical member is frictionally engaged with the photoreceptor. A cylindrical body made of synthetic resin that is triboelectrically charged with a polarity opposite to that of the residual toner on the surface of the photoconductor is coated with a cylindrical body, and the surface of the cylindrical body is pressed against the surface of the photoconductor and rotated while sliding and rubbing. Some devices are designed to physically and electrostatically remove residual toner on the body surface. In a roller-type cleaning member having such a configuration, it is especially important that the elastic cylindrical member and the synthetic resin cylindrical body be firmly crimped together (at least crimped to the extent that no loosening occurs between the cylindrical body and the elastic cylindrical member). If this pressure force is weak, the synthetic resin cylindrical body will twist and wrinkle during use of the cleaning member, and the removed residual toner will accumulate between these wrinkles, causing the residual toner on the photoreceptor to accumulate. This not only reduces the cleaning ability but also has the adverse effect of significantly damaging the surface of the photoreceptor.

As a method of covering an elastic cylindrical member with a synthetic resin cylindrical body, a cylindrical body made of a heat-shrinkable material having a larger diameter than the elastic cylindrical member is used for the synthetic resin cylindrical body, and the inside of the cylindrical body is There is a method in which the cylindrical body is completely heated and shrunk in a constant temperature atmosphere (approximately 100 to 200° C. atmosphere) with the elastic cylindrical member inserted, so that the cylindrical body is brought into close contact with the circumferential surface of the elastic cylindrical member. However, in this method, the heating time is long (approximately 5 minutes), the elastic cylindrical member is heated and expanded in the atmosphere, and the cylindrical body is tightly attached to the circumferential surface of the cylindrical member that has expanded and has a large diameter. To do this, when these members are taken out of the atmosphere and the elastic cylindrical member shrinks to its original shape as it cools, it has the disadvantage that slack occurs between the elastic cylindrical member and the cylindrical body. Ta.

Therefore, the present invention improves the above-mentioned drawbacks and manufactures a roller-type cleaning member having the above-mentioned structure in a state in which the synthetic resin cylindrical body is firmly and substantially evenly pressed against the elastic cylindrical member. It is an object of the present invention to provide a method for manufacturing a photoreceptor cleaning member that can perform the following steps.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

Prior to carrying out the method of the present invention, first, as shown in FIG. A polyethylene cylindrical body 2 (or a polyamide cylindrical body) is prepared. The diameter of the elastic cylindrical body 1 is smaller than the diameter of the cylindrical body 2. In this example, at room temperature (20 to 25°C), the outer diameter of the elastic cylindrical body 1 is approximately 43 mm, and the outer diameter of the cylindrical body 2 is approximately 50 mm. A material having a thickness of about 0.1 mm is used, and the elastic cylindrical body 1 can be inserted into the cylindrical body 2. Further, the length of the cylindrical body 2 in the axial direction is set at least so that it does not become shorter than the length of the elastic cylindrical body when the cylindrical body 2 is heated and shrunk and comes into close contact with the circumferential surface of the elastic cylindrical body, as will be described later. . The elastic cylinder 1 has a sponge hardness of 20
A metal shaft 3 is used in the center.
is inserted through the elastic cylindrical body 1, and the elastic cylindrical body 1 is fixed to the shaft 3 and maintained in a fixed shape (cylindrical body) by the shaft 3.

In manufacturing, first, the elastic cylindrical body 1 is inserted into the cylindrical body 2, and a hot air blower is used to radiate hot air from the outer surface direction of the cylindrical body 2 to evenly heat the circumferential surface of the cylindrical body 2. Heat until the temperature is approximately 100-200℃. Due to the heating, the cylindrical body thermally contracts in the radial and axial directions, and the diameter of the cylindrical body 2 decreases, causing the cylindrical body 2 to shrink.
is brought into close contact with the periphery of the elastic cylindrical body 1 in an unloaded state as shown in FIG. 2 (first step). However, in this case, the heating by the hot air blower results in localized heating, so the shrinkage of the cylindrical body 2 is uneven and uneven, and the degree of adhesion to the elastic cylindrical body 1 is not sufficient. When the photoreceptor was cleaned using the cylindrical body 2, wrinkles appeared on the cylindrical body 2, resulting in the above-mentioned drawbacks. At this time, the outer diameter of the cylindrical body 2 was approximately 43 mm, which was approximately the same as the outer diameter of the elastic cylindrical body 1 at room temperature, and no significant thermal expansion occurred in the elastic cylindrical body 1.

After the cylindrical body 2 is brought into close contact with the circumferential surface of the elastic cylindrical body 1, the elastic cylindrical body 1 whose circumferential surface is covered with the cylindrical body 2 is inserted together with the shaft 3 into a heating mold 4 as shown in FIG. Then, the heating mold 4 is heated again while applying pressure substantially uniformly in the radial direction over the entire circumferential surface of the heating mold 4.

The heating mold 4 consists of an upper mold 4A and a lower mold 4B having a groove 4a with a semicircular cross section, and the upper mold 4A is connected to the lower mold 4B in the vertical direction and the axis of the groove 4a by a link 4C. When the upper mold 4A and the lower mold 4B come into contact with each other, their respective grooves 4a are aligned and their cross sections become circular. A heating device (not shown) is placed inside the upper mold 4A and the lower mold 4B, and the grooves 4a are heated to a surface temperature of about 140 to 150°C. The diameter of the cylindrical mold hole formed by the groove 4a of the upper mold 4A and the groove 4a of the lower mold 4B is approximately 4.25 mm in this example, which is smaller than the diameter of the elastic cylindrical body 1 at room temperature. When the elastic cylindrical body 1 covering the cylindrical body 2 is inserted into the groove 4a and the upper and lower molds 4A and 4B are fitted together, the elastic cylinder 1 is compressed by the upper and lower molds 4A and 4B and has a diameter smaller than that at room temperature. compressed to a small diameter. Therefore, if the elastic cylindrical body 1 with the cylindrical body 2 coated with heat shrinkage is placed in the molds 4A and 4B and heated,
The cylindrical body 2 heat-shrinks again, but at this time, since the elastic cylindrical body 1 is in a compressed state, the cylindrical body 2 maintains this compressed diameter and the cylindrical body 2 is formed on its circumferential surface in the direction of the arrow in FIG. The elastic cylindrical body 1 is contracted in the center direction) and comes into close contact (second step). In this example, the time for heating by the molds 4A and 4B was approximately 20 seconds, and the elastic cylindrical body 1 was rotated as appropriate to prevent wrinkles from forming at the boundary between the molds 4A and 4B. . In addition, when heating with the molds 4A and 4B, silicone oil is applied to the circumferential surface of the cylindrical body 2 in advance in order to prevent adhesion between the cylindrical body 2 and the surface of the groove 4a of the mold. It is preferable to leave it there. As a result, even when the completed cleaning member is removed from the mold 4 and left to cool in the atmosphere, the elastic cylindrical body 1 does not shrink.
On the other hand, since the elastic cylindrical body 1 that has been forcibly contracted by the mold tries to return to its original shape (the shape at room temperature), the elastic circular member 1 is brought into close contact with the cylindrical body 2 due to the restoring force. It is maintained.

In the above example, a hot air blower was used to heat-shrink the material in the first step, but the cylindrical body 2 may also be heat-shrinked into the elastic cylindrical body 1 in a constant-temperature atmosphere room, and the same effect can be achieved. It is also possible to use other means.

As described above, according to the present invention, it is possible to coat the outer circumferential surface of the elastic cylindrical member with a cylindrical body of heat-shrinkable resin with strong pressure, and as a result, the photoreceptor manufactured by the method of the present invention If the cleaning member is used in an electrophotographic apparatus, the surface of the photoreceptor can be effectively cleaned.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main components of a photoconductor cleaning member to which the present invention is applied, FIG. 2 is an end view of the cleaning member in one step of the method of the present invention, and FIG. 3 is a diagram for carrying out the method of the present invention. A perspective view of the equipment used for
It is. 1... Elastic cylindrical body, 2... Cylindrical body, 3... Shaft,
4... Heating mold.

Claims (1)

[Claims] 1. In a method for manufacturing a photoreceptor cleaning member configured by covering an outer circumferential surface of an elastic cylindrical member with a cylindrical body made of heat-shrinkable synthetic resin, the method includes: A first step of heat-shrinking the cylindrical body to bring it into close contact with the circumferential surface of the elastic cylindrical member; and a first step of heating and shrinking the cylindrical body to bring the cylindrical body into close contact with the circumferential surface of the elastic cylindrical member; A second step of further heating and shrinking the cylindrical body in a state in which the cylindrical body is compressed to a smaller diameter than that of the cylindrical body to bring the cylindrical body into close contact with the circumferential surface of the compressed elastic cylindrical member.
A method for manufacturing a photoreceptor cleaning member, comprising the steps of: